In a cellular wireless communication system, such as a code division multiple access (CDMA) system for instance, base stations are positioned throughout a coverage area and emit radio frequency radiation patterns that define cells. Mobile stations operating in a given cell may then wirelessly communicate with the serving base station, and the base station may provide connectivity with further network components such as switches and gateways that connect with transport networks.
In a CDMA system, each cell is typically divided into a number of sectors, each of which is identified by a specific pseudo-noise offset (i.e., “PN offset”) of a specific spreading sequence that is used to encode communications with mobile stations operating in the cell. At any given instant, a mobile station may thus operate in a given sector, and may thereby communicate with the serving base station using the PN offset of that sector. (In practice, an idle mobile station may communicate on a single PN offset (i.e., in a single sector) at once; an active mobile, on the other hand, might communicate on multiple PN offsets (i.e., in multiple sectors) at once, although a dominant one of those active PN offsets might be the focus of communications at any given moment).
In some wireless networks, the cells may not seamlessly cover an entire area, so there may be a “gap” in coverage between cells. To help solve this problem, a wireless carrier may install repeaters that function to extend the range of a given cell or sector. Service providers use various types of repeaters, including fiber-fed repeaters and wireless repeaters. Fiber-fed repeaters are connected to the base station with fiber optic cable while wireless repeaters communicate with a base station wirelessly. A repeater may be positioned between a mobile station and a base station to intercept signals sent between them. The repeater may amplify the power of these intercepted signals and send amplified versions of these signals to the mobile station or the base station. Therefore, the repeater may effectively extend the range of a given cell by boosting signals between a mobile station and a base station.
Service providers may use repeaters to create a distributed antenna system (DAS), where a number of repeaters are used to enlarge the area covered by sector. In a DAS, each BTS may be connected to a group of repeaters that operates to repeat signals between the BTS and mobile stations. This group of repeaters (and possibly the BTS as well) may radiate to define a sector in a radio access network. Unfortunately, even with the use of repeaters to create a DAS, gaps in coverage and/or areas with low signal strength still exist. An improvement is therefore desired.